Understanding the "Origin is Not Allowed by Access-Control-Allow-Origin" Error
When making AJAX requests from JavaScript, you may encounter the "Origin is not allowed by Access-Control-Allow-Origin" error. This error stems from the "same-origin policy," a security measure in JavaScript that restricts cross-origin requests.
Causes of the Error
The error occurs when attempting to make a request from your JavaScript code to a server with a different protocol (e.g., http:// vs. https://), host (e.g., example.com vs. subdomain.example.com), or port (e.g., port 80 vs. port 8080).
Resolution
To resolve this error, you have several options:
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